This was originally a saxophone number, accompanied by ARP String Ensemble, Fender Rhodes piano and drums.
It was never released publicly so sadly remains nameless to me, but the track made its screen debut in Eurociné’s prison thriller, ‘Helga, She Wolf Of Stilberg’, directed by Alain Payet in 1977.
This film was co-produced by Richard Allan’s ‘Les Films Du Saphir’, and the same music also featured in some of his own X-films of the period, such as ‘Annonces Spéciales Pour Couples Vicieux’ in 1977 (again directed by Alain Payet.)
From there, this particular track was sourced in several more Eurociné productions (usually in bedroom scenes), but it was used most effectively in Jesús Franco’s ‘Aberraciones Sexuales De Una Mujer Casada’, in 1980, (as well as its Eurociné off-shoot, ‘Cecilia’, in 1983.) In one scene, Muriel Montossé and Antonio Mayans discuss their marital problems on the terrace of their villa, (Palácio de Monserrate, Sintra), while the morning mist rises in front of them, and this melody plays out in the background, completely naturally.
Franco obviously liked this theme enough to include in several more of his films, carte-blanche –
‘Eugenie (Historia De Una Perversión)’, 1980, included a version of this track with added vocals, (possibly the voice of Franco’s nephew, Carlos Franco, under his pseudonym of ‘Carloto Perla.’)
‘La Chica De Las Bragas Transparentes’, 1980 (again it became the title theme.)
‘Confesiones Íntimas De Una Exhibicionista’ (co-directed by Lina Romay in 1981.)
I am just an amateur and do not own any of this.